dr. martin t. auer mtu department of civil & environmental engineering surface water quality
Post on 20-Jan-2016
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Dr. Martin T. AuerMTU Department of Civil & Environmental Engineering
Surface Water Quality
• water supply
• wastewater discharge
• recreation
Surface Water Quality Management
Add Clark
In A Watershed Everyone Lives Downstream
• water supply
• wastewater discharge
• recreation
Surface Water Quality Management
Temperature and the Density of Water
1.0000
0.9995
0.9990
0.9985
0.9980
0.9975
0.9970
0.9965
0.9960
0.99550.9950
Den
sity
(g∙
cm3 )
0 5 10 15 20 25 30
Temperature (°C)
MaximumDensity3.94 °C
Thermal Stratification
spring summer
Temperature (°C)
Thermal Stratification
Seasonality in Stratification and Mixing
= °C
Dollar Bay - Temperature
0
1
2
3
4
5
6
7 8
Dep
th (
m)
0 5 10 15 20
Temperature (°C)
0
1
2
3
4
5
6
7
8
Dep
th (
m)
M A M J J A S O N D
You are what you eat. For example, there’s this lake …
… and there’s that lake.
Oligotrophic
Low in algae
High transparency
Cold water fishery
Eutrophic
High in algae
Low transparency
Warm water fishery
Trophic State
The Limiting Nutrient Concept
The Supplies
The Product
The Divided Lake
Productivity and Oxygen
Trophic State and Oxygen Profiles
Orthograde
0
2
4
6
8
10
12
14
16
18
20
0 5 10 15 20 25
De
pth
(m
)
Clinograde
0
2
4
6
8
10
12
14
16
18
20
0 5 10 15 20 25
De
pth
(m
)
Oligotrophic Lake Eutrophic Lake
Temperature (°C) Temperature (°C)
Dollar Bay - Temperature
0
1
2
3
4
5
6
7 8
0 5 10 15 20
Temperature (°C)
0
1
2
3
4
5
6
7
8
Dep
th (
m)
M A M J J A S O N D
Dollar Bay – Dissolved Oxygen
Dep
th (
m)
0
1
2
3
4
5
6
7
8
0 2 4 6 8 10 12
Dissolved Oxygen (mg∙L-1)
M A M J J A S O N D
Onondaga Lake – Dissolved Oxygen
Oneida Lake – Dissolved Oxygen
Lake Erie – Dissolved Oxygen
Gulf of Mexico – Dissolved Oxygen
Aerobic and Anaerobic Metabolism
2
3
4
3
24
2
2
2
2
2
2 3
2 2
2 2
2 2
2 2
2 2
2
2
2
42 2
( )
( )
( )
( )
( )
( )
N HCO
M
CO H O
CO H O
CO H O
CO H
O
NO
M
C H O
C H O
C H O
C H O
C H O
C H O
O
CO
n
Fe
H
n
F
S
CH
e
H O
CO
SO
Aerobic (oxygen available)
Anaerobic (oxygen not available)
Oligotrophic
Low in nutrients, TP<10
Low in algae
Oxygen at saturation
High transparency
Cold water fishery
Deep lakes with steep sides and infertile, often rocky watersheds.
Eutrophic
High in nutrients, TP>20
High in algae
Oxygen (+, epi), (-, hyp)
Low transparency
Warm water fishery
Shallow lakes with gently sloping sides and cultivated, fertile watersheds.
Natural Eutrophication
Cultural Eutrophication
Lakes: Loss of Beneficial Use
• Nutrients – aesthetics, recreation, drinking water
• Microorganisms – recreation, drinking water
• Toxics – wildlife, drinking water• heavy metals: cadmium, lead, mercury• synthetic organic chemicals: DDT, PCB, dioxin
Engineering Approaches for Lake Management(Phosphorus)
1. Lake Protection• Point source control (advanced waste treatment)• Nonpoint source control
Engineering Approaches for Lake Management(Phosphorus)
1. Lake Protection• Point source control• Nonpoint source control (land use management)
Engineering Approaches for Lake Management(Phosphorus)
2. Diversion
Onondaga Lake
Seneca River
METRO
Engineering Approaches for Lake Management(Phosphorus)
3. Hypolimnetic Aeration
Support RaftGas Vent
SupportCables
ContactChamber
Air Line &Diffuser
Ballast
Engineering Approaches for Lake Management(Phosphorus)
4. Sediment Inactivation
Engineering Approaches for Lake Management(Phosphorus)
5. Dredging
Engineering Approaches for Lake Management(Phosphorus)
6. Algicides
Engineering Approaches for Lake Management(Phosphorus)
7. Biomanipulation
River Water Quality
Add Clark
In A Watershed Everyone Lives Downstream
Biochemical Oxygen Demand
BOD exerted, y
BOD remaining, L
Dissolved Oxygen Saturation and Deficit
6.0
8.0
10.0
12.0
14.0
16.0
0 5 10 15 20 25 30 35
Temperature (°C)
Dis
solv
ed O
xyg
en (
mg
/L,
pp
m)
Change in oxygen concentration =
inputs from reaeration – losses to deoxygenation
Dissolved Oxygen Sag Curve
Stream Zones and Biota
Organism Diversity and Abundance